Activity: Studying Ferns and Horsetails

Goals:

1. To study the structure of ferns and identify their

parts.

2. To examine fern fronds to discover reproductive

structures called spores.

3. To examine a relative of the ferns, the horsetails.

Background Information: Ferns are non-flowering vascular plants. More than any other group they are a visible link to our geological past. Their origins date back 400 million years to the emergence of the first vascular plants. During the age of dinosaurs, ancient ferns grew to the size of trees. The warm, moist conditions of the Carboniferous period allowed plants like ferns to dominate the landscape. They are considered to be the principle contributors to the formation of today’s coal deposits.

Ferns and their relatives can be found in almost every country and ecosystem of the world, but their numbers (11,000 species) are very small when compared to the seed plants (250,000 species).

Like other vascular plants, ferns have true leaves, stems, and roots. Unlike more sophisticated vascular plants, ferns reproduce using spores. Ferns must reproduce in standing water so that their sperm cells can swim to eggs. Therefore, ferns prefer to live in environments that are moist.

The leaf of a fern is often divided into many smaller parts that look like miniature leaves. This gives fern fronds a delicate structure. The roots of stems are brown, furry structures that lie on the ground or even under the soil. Their roots are wiry structures attached to the stems.

Horsetails are included in the group of fern allies. Although they are not considered closely related, they do share similar life cycles. (This text is copied and/or paraphrased from Ferns and Fern Allies at .)

Materials: At least two varieties of fern fronds and/or whole plants, horsetail specimens, hand lenses, colored pencils

Procedure:

Rotate through the various stations listed below and complete the indicated activity described at each station.

Station 1: Ferns

  1. Using a hand lens, examine the structure of the ferns.
  2. Notice the shades of color, textures, and shapes of the fronds. Fronds are also called leaves or blades.
  3. Examine the stem-like structure that is in the center of the frond. This is called an axisor rachis, not a stem.
  4. Your fern specimen may have a leaf that is divided into smaller leaves. These are called leaflets.
  5. Leaflets may be further divided into tiny teeth.
  6. The stem of the fern connects the frond to the furry root-like rhizomes.
  7. Examine the roots of a fern plant if available. They are black and wiry.
  8. Look for spore cases called sori on the undersides of the fronds.
  9. Draw an illustration of one of the fern specimens. Label the stem and frond and any other parts you observe.
  10. Draw a small portion of a frond with spore cases. Label one spore case/sori.
  11. Label each drawing using the name of the species.
  12. Answer the questions that follow using your textbook.

Hyperlinks: Fern Illustration; Fern with Sori Image; Fern Basics

  1. Drawing/Labels

Illustration of a Fern Frond with Leaflets / Leaflet Specimen with and/or without Sori
  1. Questions:
  1. What two characteristics do ferns and their relatives, the horsetails and the club mosses share? (p.131)
  1. Ferns and their relatives need to grow in moist surroundings. Why is this necessary? Be sure to indicate the idea of reproduction using spores (p. 132)

Station 2: Horsetails

  1. Using a hand lens, examine the structure of a horsetail specimen.
  2. Notice the long, slender, hollow stems.
  3. Notice how the stems are divided into segments by bands called nodes. The nodes contain rough structures called teeth.
  4. It may be possible to see the curving tufts of rhizomes attached to wiry roots.
  5. Draw an illustration of a specimen, and label as many parts as you can find.
  6. Write a fact about horsetails.

Hyperlinks: Horsetail Structure; Horsetail Article

  1. Drawing/Labels

Illustration of a Horsetail
  1. Facts:Write two facts about horsetails using page134 in your textbook or the resource (Horsetail Article) provided at your station.

1.

2.

Station 3: Fiddleheads

  1. Ferns unfold in a very unusual way. A young, unfolded fern is called

a fiddlehead. Study the fiddleheads on display.

2. Draw an illustration of a fiddlehead.

3. Write a fact about fiddleheads.

  1. Drawing

Illustration of a Fiddlehead
  1. Fact: Use the resource (Fiddleheads) provided at your station and write one fact about fiddleheads.

Station 4: United Streaming Video Clip

Observe the video clip and fill in the following statements:

  1. Ferns and horsetails are the first plants to have a system inside their bodies that

carry ______and nutrients.

  1. Today, only ______species of ferns and horsetails exist.
  2. Ferns and horsetails dominated plant life on Earth ______million years ago, a time when the first insects appeared and amphibians began to walk on Earth.
  3. Ferns and horsetails reproduce by making ______blown by the wind.
  4. Reproduction in ferns and horsetails requires ______; that is why they are found in moist places.

Station 5: Fern Website

  1. Log on to the American Fern Society at

and click on Fern Basics.

  1. Write 3 new facts you learned about ferns.

a.

b.

c.